Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant
under any of the following provisions (see General Instruction A.2. below):

¨

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

On January 24, 2013, Cincinnati Bell Inc. (Cincinnati Bell) issued a press release announcing that CyrusOne Inc.,
which owns and operates Cincinnati Bells former data center business (CyrusOne), has completed its previously announced initial public offering of its common stock. CyrusOne sold 18,975,000 shares of its common stock in
total in the offering, which included 2,475,000 shares of common stock sold pursuant to the option granted to the underwriters by CyrusOne, which was exercised in full prior to the closing. A copy of the press release is furnished herewith as
Exhibit 99.1.

ITEM 9.01  FINANCIAL STATEMENTS AND EXHIBITS

(d) Exhibits

Exhibit

No.

Description

99.1

Press Release dated January 24, 2013

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.